Aminoacyl-tRNA synthetases are at the center of the question of the origin of life 1,2. For that reason, proteins that resemble tRNA synthetases are of great interest. The large number of sequences of proteins emerging from the various genome projects has provided opportunity to search for new sequences that are 'synthetase-like'. Several have been identified and, although the functions of many...

Non-ribosomal peptide products often contain modified building blocks or post-assembly line alterations of their peptide scaffolds with some of them being crucial for biological activity. These reactions such as halogenation, hydroxylation or glycosylation are mostly catalyzed by individual enzymes associated with the respective biosynthesis cluster. The versatile nature of these chemical modif...

Macrocyclization is a common feature of natural product biosynthetic pathways including the diverse family of ribosomal peptides. Microviridins are architecturally complex cyanobacterial ribosomal peptides that target proteases with potent reversible inhibition. The product structure is constructed via three macrocyclizations catalyzed sequentially by two members of the ATP-grasp family, a uniq...